Gun cartridge

ABSTRACT

A gun cartridge which includes a projectile having a body which is substantially reduced in cross section intermediate its length. A multiple-part casement fits around the projectile and is snugly seated within a casing of the ammunition cartridge and serves to center the projectile in the casing. The multiple-part casement has parts fitting in said reduced projectile part and is adapted to accompany the projectile from the casing and to fall away from the projectile during flight.

United States Patent 72 Inventor Grover E- He dri 3,033,116 5/1962 Critcher et al. 102 93 2241 Lake Nlles, Mlch- 49120 3,450,050 6/1969 Robinson l02/38 x 21] Appl. No. 767,995 3,148,472 9/1964 Hegge et al. .0 102 93 x [22] Flled oc 1 3,157,126 11/1964 Blondeau 102/93 X [45] Patented 1971 Primary Examiner--Robert F. Stahl Atl0rney-O1tsch & Knoblock [54] GUN CARTRIDGE 1 Claim, 7 Drawing Figs.

[52] US. Cl 102/38, ABSTRACT; A gun cartridge which includes a projectile hav- 102/93 ing a body which is substantially reduced in cross section in- [51] Int. Cl Ezlb 43/06 immediate its length, A multiple-part casement fits around the [50] Fleld of Search 102/93, 94, r jectile and is snu ly seared within a casing of the ammuni- 38, tion cartridge and serves to center the projectile in the casing. The multiple-part casement has parts fitting in said reduced [56] References C'ted projectile part and is adapted to accompany the projectile UNITED STATES PATENTS from the casing and to fall away from the projectile during 2,306,140 12/1942 Reed 102/93 flight.

l 1 1 2O \1 \\\\\\\xv\ SUMMARY OF THE INVENTION This invention relates to an improved gun cartridge, including its projectile, and has particular application to shotgun slug shells.

This invention concerns an improvement to a gun cartridge which comprises a casing having a tubular sidewall, an end wall having a recess therein, a primer disposed within said end wall recess, a projectile seated within said casing at the open end thereof and defining a chamber in said casing, and a propellant charge disposed within said chamber. The improvement ofthis invention concerns the projectile whose body portion is substantially reduced in cross section intermediate its length. A multiple-part casement encircles the projectile and snugly seats within the casing. The multiple-part casement has a part seating in said reduced projectile body portion and is adapted to accompany the projectile upon its discharge from the casing and to fall away from the projectile when it is in flight.

The projectile or slug of .the standard shotgun slug shell usually has a lead body with a snub head and is of uniform outer diameter except for exterior helical ribs whichare used to induce rotation of the projectile as it leaves the gun bore. Projectiles of this type are of generally poor accuracy and are susceptible to deformation and resultant erratic behavior when striking underbrush or similar obstructions during flight to a target.

The projectile of this invention is preferably formed from steel or'ferrous metal. The steel projectile is prevented from contact with the inner surface of the gun barrel by the multi ple-part casement during its passage through the barrel so as not to scar the barrel bore. The casement is preferably formed of a plastic material having a low coefficient of friction-to permit the projectile to be discharged from the gun at a maximum velocity. Additionally, the shape of the projectile improves its trajectory and speed. In comparing the performance of a shotgun shell having a standard lead projectile and a shotgun shell constructed in accordance with the teachings of this invention, tests have shown that when fired at a l20-yard target with the same amount of powder charge, the lead shotgun projectile drops approximately 6 inches during flight and the steel projectile encased by the aforedescribed plastic casement drops only approximately 2 inches.

Accordingly, it is a purpose of this invention to provide a gun cartridge having a projectile in which the body portion thereof is substantially reduced in cross section intermediate its length and is substantially encircled by a multiple-part casement of complementary shape which seats snugly within the casing of the gun cartridge.

It is a further purpose of this invention to provide a gun cartridge having a steel projectile.

Another object of this invention is to provide a cartridge for use in a shotgun which utilizes a slug of high accuracy and high impact velocity.

Another object of this invention is to provide a cartridge for use in a shotgun which is of economical construction.

Other objects of this invention will become apparent upon a reading of the invention s description.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an axial sectional view of one embodiment of a gun cartridge of this invention.

FIG. 2 is an end view of the gun cartridge of FIG. 1 as viewed from the right in FIG. 1.

FIG. 3 is an exploded perspective view of the projectile and casement utilized in the gun cartridge of FIG. 1.

FIG. 4 is a cross-sectional view taken along Line 4-4 of FIG. 1.

FIG. 5 is a side view of the projectile utilized in the gun cartridge of FIG. I.

FIG. 6 is a side view of one part of the projectile casement as viewed interiorly.

FIG. 7 is an axial sectional view of a modified projectile-and casement for use in a gun cartridge.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The preferred embodiments illustrated are not intended to be exhaustive or to limit the invention to the precise forms disclosed. They are chosen and described in order to best explain the principles of the invention, its application and practical use, to thereby enable others skilled in the art to best utilize the invention.

FIGS. 1-6 illustrate one embodiment of the gun cartridge of this invention. The casing of the cartridge is designated by numetal 10 and is preferably formed of molded plastic material and includes a tubular sidewall 12, preferably cylindrical in configuration, and an end wall 14. Sidewall l2 of casing 10includes a thin-wall portion 18 at its free or open end 20 which joins thick-wall portion 16. Portions l6 and 18 are of uniform outer dimension and are joined'by an intermediate interior part defining first and second stepped internal shoulders 22 and 24. A narrow small inner circumferential rib 26 projects from thick-wall portion 16 and partially defines shoulder 22. End wall 14 of casing 10 includes an outwardly projecting circumferential flange or rim l3 and a central inwardly projecting cup-shaped part 28 which is separated'from-tubular por' tion 16 by an annular groove 30. The-base of part 28-hasa bore 34 centrally thereof. The bore 34 of part 28 opens at the outer face of wall 14 and a primer 36 is received therein.

The projectile in the gun cartridge of this invention has a body portion which is substantially reduced in cross section intermediate its length to improve the stability and increase the speed of the projectile. A preferred embodiment of such a projectile is illustrated in the drawings and is designated by the numeral 38.

Projectile 38 includes a head portion 40 and a coaxial body portion 46. Head portion 40 includes a conical part 42 which terminates in a rounded tip 43. Body portion '46'of projectile 38 includes a short cylindrical part 41, a conical part 48 separated from cylindrical part 41 by a circumferential groove 45, a cylindrical part 50 and a cylindrical projection 54 separated from cylindrical part 50 by a circumferential groove 58. Cylindrical part 4.1 has an outer diameter slightly less than the inner diameter of thin-wall portion 18 of casing 10 and a substantially flat rear end face 44 defined by groove 45. The degree of taper of conical parts 42 and 48 of projectile 38 are preferably the same but may differ.

Cylindrical part 50 has a rear end face 52 which is defined by groove 58 and an outer diameter which is preferably less than the outer diameter of cylindrical part 41 but which may be of the same dimension. Cylindrical projection 54 of body portion 46 has an outer diameter which is substantially the same as the inner diameter of thick-wall portion 16 of casing 10. Projectile 38 has an elongated axial recess or bore 60 having an enlarged open end part 62 within projection 54 thereof and terminating within head portion 40. It is to be understood that the improved stability and increased speed of projectile 38 is largely the result of circumferential groove 45 in body portion 46. Groove 58 provides a recess into which inner rib 26 of casing 10 is received so as to releasably anchor the projectile within the casing. It may be desirable in some circumstances to eliminate cylindrical parts 41 and 50 and cylindrical projection 54 of projectile 38.

The projectile of this invention is preferably formed of steel but may be formed of other similar material and may be coated with a tetrafluoroethylene polymer or similar material. It is to be further understood that the projectile of this invention need not be circular in cross section. Also the projectile of this invention may be of solid construction with no axial recess. Additionally, the circumferential stabilizing groove in the body portion of the projectile may be interrupted by circumferentially spaced, longitudinally directed ribs.

A spacer or casement 64, preferably formed of plastic, encircles projectile 38. Casement 64 has an outer surface 66 which fits snugly and slidably within portion 18 of cartridge casing and on inner surface or bore 68 which is substantially complementary to the shape of projectile 38. Casement 64 is preferably longitudinally divided into a plurality of symmetrical parts 64A to permit casement 64 to fall away from projectile 38 after the projectile 38 leaves the barrel of the gun and is in flight. Parts 64A of casement 64 preferably completely encircle the projectile 38 and extend from a position at or adjacent to face 52 to and preferably slightly beyond tip 43 of the projectile as shown in FIG. 1. The forward end face 74 of casement 64 is preferably interrupted by a central aperture 76 which exposes projectile tip 43 and which permits the ingress of air to and around the tip 43 during flight of the projectile to assist in stripping the casement 64 from the projectile. Although the forward end face 74 of casement 64 is illustrated as being substantially flat, it is to be understood that it can be tapered or of some other configuration.

The projectile casement need not entirely enclose the sides of the projectile but can be composed of parts circumferentially spaced about the projectile so as to support and position the projectile in the casing and to prevent contact of the projectile with the barrel of the gun upon detonation of the propellant charge. Also the casement may be of one-piece construction having a rear end wall and integral circumferentially spaced forwardly extending flexible fingers which engage and project longitudinally along the sides of the projectile.

Casing l0, projectile 38, and casement 64 are of such size that, with casement 64 encircling projectile 38 and snugly seating within portion 18 of casing 10, the shoulder 56 of projectile 38 abuts rib 26 of casing 10 so as to retain the projectile and casement within the shell. If desired, thick-wall portion 16 may be slightly reduced in thickness at 72 rearwardly of rib 26 to snugly receive projection 54 of projectile 38. It is to be understood that the means for retaining casement 64 and projectile 38 within casing 10 can vary.

The projection 54 of the projectile terminates spaced from casing end parts 14 and 28 to define a propellant chamber 76. Recess 60 in projectile 38 communicates with the propellant chamber 76. A propellant charge 77 is disposed within propellant chamber 76.

F IG. 7 illustrates a modified construction of the casement illustrated in FIGS. l6. In this construction the casement 64 entirely encloses projectile 38 with the exception of an opening exposing the tip 43. The casement 64' receiving projectile 38 includes an end wall 75 spanning the open end of projection 54 of the projectile. Casement 64 with enclosed projectile 38 is press fit into the thin-wall portion of a modified shell casing from which rib 26 is omitted and is abutted against a shoulder separating the thin-wall and thick-wall portions of the casing. Additionally, casement 64' may be slidably received within the modified shell casing and the receiving end of the casing folded or crimped inwardly over the forward end of the casement.

What I claim is:

1. In a cartridge for use in a shotgun comprising a casing having a tubular sidewall and an end wall, a projectile disposed within said casing spaced from said end wall and defining with said casing a propellant chamber, a propellant charge disposed within said propellant chamber, a primer carried by said casing end wall, a multiple-part casement substantially encircling said projectile and snugly received within said casing, said casement releasably interlocked with said projectile so as to accompany said projectile out of said shotgun upon detonation of said propellant charge and thereafter separate from said projectile during flight, the improvement wherein said projectile includes a head portion and a coaxial body portion, said body portion having a part intermediate its length of reduced cross-sectional dimension and a rear end wall, said projectile having an axial recess which opens at said rear end wall of said body portion. 

1. In a cartridge for use in a shotgun comprising a casing having a tubular sidewall and an end wall, a projectile disposed within said casing spaced from said end wall and defining with said casing a propellant chamber, a propellant charge disposed within said propellant chamber, a primer carried by said casing end wall, a multiple-part casement substantially encircling said projectile and snugly received within said casing, said casement releasably interlocked with said projectile so as to accompany said projectile out of said shotgun upon detonation of said propellant charge and thereafter separate from said projectile during flight, the improvement wherein said projectile includes a head portion and a coaxial body portion, said body portion having a part intermediate its length of reduced cross-sectional dimension and a rear end wall, said projectile having an axial recess which opens at said rear end wall of said body portion. 